In general, a UAV is an aircraft which flies without a human pilot on-board. A UAV recognizes a path of flight thereof based on programmed instructions provided to the UAV by a remote control station or by UAV embedded controllers. With advancement in aviation technology, utilization of UAVs, also known as “drones”, for various urban civilian and rural civilian applications is increasing. For example, the UAV is being utilized for urban civilian applications such as surveillance, fire brigades, disaster control, emergency response crews, while remote rural civilian applications include periodic monitoring of long linear infrastructures towards critical utilities, such as power line, oil/gas pipelines, and so on. Other advanced applications of UAVs usage include weather observation, topographical survey, and various military applications.
In order to assist a UAV in landing, various techniques have been implemented. For example, an external controller is employed that may assist the UAV to land at a particular point or location. In certain scenarios, such point/location is identified by implementing a marker based technique, wherein a marker such as an “H” shaped marker or a marker having concentric rings may be placed at the landing location. The UAV includes a camera that is configured to identify the marker and land thereon.
The inventors here have recognized several technical problems with such conventional systems, as explained below. In a marker based technique, for the camera to accurately detect the marker, the marker should be fully within the camera field of view (FOV) so that it can be fully imaged and identified. Moreover, when the UAV is on a descend path, the image of the marker as captured by the camera keeps changing, thereby rendering the detection of the marker inefficiently.